Description

In the first synopsis form, the getconf utility will write to the
standard output the value of the variable specified by system_var, in accordance
with specification if the -v option is used.

In the second synopsis form, getconf will write to the standard output
the value of the variable specified by path_var for the path specified
by pathname, in accordance with specification if the -v option is used.

In the third synopsis form, config will write to the standard output
the names of the current system configuration variables.

The value of each configuration variable will be determined as if it
were obtained by calling the function from which it is defined to
be available. The value will reflect conditions in the current operating environment.

Options

The following options are supported:

-a

Writes the names of the current system configuration variables to the standard output.

-vspecification

Gives the specification which governs the selection of values for configuration variables.

Operands

The following operands are supported:

path_var

A name of a configuration variable whose value is available from the pathconf(2) function. All of the values in the following table are supported:

LINK_MAX

NAME_MAX

_POSIX_CHOWN_RESTRICTED

MAX_CANON

PATH_MAX

_POSIX_NO_TRUNC

MAX_INPUT

PIPE_BUF

_POSIX_VDISABLE

pathname

A path name for which the variable specified by path_var is to be determined.

system_var

A name of a configuration variable whose value is available from confstr(3C) or sysconf(3C). All of the values in the following table are supported:

ARG_MAX

BC_BASE_MAX

BC_DIM_MAX

BC_SCALE_MAX

BC_STRING_MAX

CHAR_BIT

CHARCLASS_NAME_MAX

CHAR_MAX

CHAR_MIN

CHILD_MAX

CLK_TCK

COLL_WEIGHTS_MAX

CS_PATH

EXPR_NEST_MAX

HOST_NAME_MAX

INT_MAX

INT_MIN

LFS64_CFLAGS

LFS64_LDFLAGS

LFS64_LIBS

LFS64_LINTFLAGS

LFS_CFLAGS

LFS_LDFLAGS

LFS_LIBS

LFS_LINTFLAGS

LINE_MAX

LONG_BIT

LONG_MAX

LONG_MIN

MB_LEN_MAX

NGROUPS_MAX

NL_ARGMAX

NL_LANGMAX

NL_MSGMAX

NL_NMAX

NL_SETMAX

NL_TEXTMAX

NZERO

OPEN_MAX

POSIX2_BC_BASE_MAX

POSIX2_BC_DIM_MAX

POSIX2_BC_SCALE_MAX

POSIX2_BC_STRING_MAX

POSIX2_C_BIND

POSIX2_C_DEV

POSIX2_CHAR_TERM

POSIX2_COLL_WEIGHTS_MAX

POSIX2_C_VERSION

POSIX2_EXPR_NEST_MAX

POSIX2_FORT_DEV

POSIX2_FORT_RUN

POSIX2_LINE_MAX

POSIX2_LOCALEDEF

POSIX2_RE_DUP_MAX

POSIX2_SW_DEV

POSIX2_SYMLINKS

POSIX2_UPE

POSIX2_VERSION

POSIX_ALLOC_SIZE_MIN

POSIX_REC_INCR_XFER_SIZE

POSIX_REC_MAX_XFER_SIZE

POSIX_REC_MIN_XFER_SIZE

POSIX_REC_XFER_ALIGN

POSIX_V6_ILP32_OFF32

POSIX_V6_ILP32_OFF32_CFLAGS

POSIX_V6_ILP32_OFF32_LDFLAGS

POSIX_V6_ILP32_OFF32_LIBS

POSIX_V6_ILP32_OFFBIG

POSIX_V6_ILP32_OFFBIG_CFLAGS

POSIX_V6_ILP32_OFFBIG_LDFLAGS

POSIX_V6_ILP32_OFFBIG_LIBS

POSIX_V6_LP64_OFF64

POSIX_V6_LP64_OFF64_CFLAGS

POSIX_V6_LP64_OFF64_LDFLAGS

POSIX_V6_LP64_OFF64_LIBS

POSIX_V6_LPBIG_OFFBIG

POSIX_V6_LPBIG_OFFBIG_CFLAGS

POSIX_V6_LPBIG_OFFBIG_LDFLAGS

POSIX_V6_LPBIG_OFFBIG_LIBS

POSIX_V6_WIDTH_RESTRICTED_ENVS

SYMLINK_MAX

SYMLOOP_MAX

_POSIX2_BC_BASE_MAX

_POSIX2_BC_DIM_MAX

_POSIX2_BC_SCALE_MAX

_POSIX2_BC_STRING_MAX

_POSIX2_CHARCLASS_NAME_MAX

_POSIX2_CHAR_TERM

_POSIX2_COLL_WEIGHTS_MAX

_POSIX2_C_BIND

_POSIX2_C_DEV

_POSIX2_C_VERSION

_POSIX2_EXPR_NEST_MAX

_POSIX2_FORT_DEV

_POSIX2_FORT_RUN

_POSIX2_LINE_MAX

_POSIX2_LOCALEDEF

_POSIX2_PBS

_POSIX2_PBS_ACCOUNTING

_POSIX2_PBS_CHECKPOINT

_POSIX2_PBS_LOCATE

_POSIX2_PBS_MESSAGE

_POSIX2_PBS_TRACK

_POSIX2_RE_DUP_MAX

_POSIX2_SW_DEV

_POSIX2_UPE

_POSIX2_VERSION

_POSIX_ADVISORY_INFO

_POSIX_AIO_LISTIO_MAX

_POSIX_AIO_MAX

_POSIX_ARG_MAX

_POSIX_ASYNC_IO

_POSIX_BARRIERS

_POSIX_CHILD_MAX

_POSIX_CLOCKRES_MIN

_POSIX_CLOCK_SELECTION

_POSIX_CPUTIME

_POSIX_DELAYTIMER_MAX

_POSIX_HOST_NAME_MAX

_POSIX_IPV6

_POSIX_JOB_CONTROL

_POSIX_LINK_MAX

_POSIX_LOGIN_NAME_MAX

_POSIX_MAX_CANON

_POSIX_MAX_INPUT

_POSIX_MONOTONIC_CLOCK

_POSIX_MQ_OPEN_MAX

_POSIX_MQ_PRIO_MAX

_POSIX_NAME_MAX

_POSIX_NGROUPS_MAX

_POSIX_OPEN_MAX

_POSIX_PATH_MAX

_POSIX_PIPE_BUF

_POSIX_PRIO_IO

_POSIX_RAW_SOCKETS

_POSIX_READER_WRITER_LOCKS

_POSIX_REGEXP

_POSIX_RE_DUP_MAX

_POSIX_RTSIG_MAX

_POSIX_SAVED_IDS

_POSIX_SEM_NSEMS_MAX

_POSIX_SEM_VALUE_MAX

_POSIX_SHELL

_POSIX_SIGQUEUE_MAX

_POSIX_SPAWN

_POSIX_SPIN_LOCKS

_POSIX_SPORADIC_SERVER

_POSIX_SSIZE_MAX

_POSIX_SS_REPL_MAX

_POSIX_STREAM_MAX

_POSIX_SYMLINK_MAX

_POSIX_SYMLOOP_MAX

_POSIX_SYNC_IO

_POSIX_THREAD_ATTR_STACKADDR

_POSIX_THREAD_ATTR_STACKSIZE

_POSIX_THREAD_CPUTIME

_POSIX_THREAD_DESTRUCTOR_ITERATIONS

_POSIX_THREAD_KEYS_MAX

_POSIX_THREAD_PRIORITY_SCHEDULING

_POSIX_THREAD_PRIO_INHERIT

_POSIX_THREAD_PRIO_PROTECT

_POSIX_THREAD_PROCESS_SHARED

_POSIX_THREAD_SAFE_FUNCTIONS

_POSIX_THREAD_SPORADIC_SERVER

_POSIX_THREAD_THREADS_MAX

_POSIX_TIMEOUTS

_POSIX_TIMER_MAX

_POSIX_TRA_POSIX_TIMER_MAXCE

_POSIX_TRACE_EVENT_FILTER

_POSIX_TRACE_EVENT_NAME_MAX

_POSIX_TRACE_INHERIT

_POSIX_TRACE_LOG

_POSIX_TRACE_NAME_MAX

_POSIX_TRACE_SYS_MAX

_POSIX_TRACE_USER_EVENT_MAX

_POSIX_TTY_NAME_MAX

_POSIX_TYPED_MEMORY_OBJECTS

_POSIX_TZNAME_MAX

_POSIX_VERSION

_POSIX_V6_ILP32_OFF32

_POSIX_V6_ILP32_OFFBIG

_POSIX_V6_LP64_OFF64

_POSIX_V6_LPBIG_OFFBIG

_V6_ILP32_OFF32

_V6_ILP32_OFFBIG

_V6_LP64_OFF64

_V6_LPBIG_OFFBIG

RE_DUP_MAX

SCHAR_MAX

SCHAR_MIN

SHRT_MAX

SHRT_MIN

SSIZE_MAX

STREAM_MAX

TMP_MAX

TZNAME_MAX

UCHAR_MAX

UINT_MAX

ULONG_MAX

USHRT_MAX

WORD_BIT

XBS5_ILP32_OFF32

XBS5_ILP32_OFF32_CFLAGS

XBS5_ILP32_OFF32_LDFLAGS

XBS5_ILP32_OFF32_LIBS

XBS5_ILP32_OFF32_LINTFLAGS

XBS5_ILP32_OFFBIG

XBS5_ILP32_OFFBIG_CFLAGS

XBS5_ILP32_OFFBIG_LDFLAGS

XBS5_ILP32_OFFBIG_LIBS

XBS5_ILP32_OFFBIG_LINTFLAGS

XBS5_LP64_OFF64

XBS5_LP64_OFF64_CFLAGS

XBS5_LP64_OFF64_LDFLAGS

XBS5_LP64_OFF64_LIBS

XBS5_LP64_OFF64_LINTFLAGS

XBS5_LPBIG_OFFBIG

XBS5_LPBIG_OFFBIG_CFLAGS

XBS5_LPBIG_OFFBIG_LDFLAGS

XBS5_LPBIG_OFFBIG_LIBS

XBS5_LPBIG_OFFBIG_LINTFLAGS

_XOPEN_CRYPT

_XOPEN_ENH_I18N

_XOPEN_IOV_MAX

_XOPEN_LEGACY

_XOPEN_NAME_MAX

_XOPEN_PATH_MAX

_XOPEN_SHM

_XOPEN_STREAMS

_XOPEN_VERSION

_XOPEN_XCU_VERSION

_XOPEN_XPG2

_XOPEN_XPG3

_XOPEN_XPG4

The symbol PATH also is recognized, yielding the same value as the
confstr() name value CS_PATH.

Usage

See largefile(5) for the description of the behavior of getconf when encountering
files greater than or equal to 2 Gbyte ( 231 bytes).

Examples

Example 1 Writing the Value of a Variable

This example illustrates the value of {NGROUPS_MAX}:

example% getconf NGROUPS_MAX

Example 2 Writing the Value of a Variable for a Specific Directory

This example illustrates the value of NAME_MAX for a specific directory:

example% getconf NAME_MAX /usr

Example 3 Dealing with Unspecified Results

This example shows how to deal more carefully with results that might
be unspecified:

in a C program could give different answers. The sysconf call supplies
a value that corresponds to the conditions when the program was either
compiled or executed, depending on the implementation. The system call to getconf
always supplies a value corresponding to conditions when the program is executed.

Environment Variables

See environ(5) for descriptions of the following environment variables that affect the
execution of getconf: LANG, LC_ALL, LC_CTYPE, LC_MESSAGES, and NLSPATH.

Exit Status

The following exit values are returned:

0

The specified variable is valid and information about its current state was written successfully.